2-[[4-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)-1-(piperidinyl or 1,2,3,6-tetrahydro-1-pyridinyl)]alkyl]-1H-benz[de]isoquinoline-1,3(2H)-diones

ABSTRACT

Compounds of the following formula and their acid addition salts ##STR1## wherein R 1  and R 2  are selected from hydrogen, halogen, lower alkyl, lower alkoxy, lower alkylthio, nitro, amino, trifluoromethyl, or cyano; R 3  is hydrogen or lower alkyl; R 4  and R 5  are selected from hydrogen, halogen, lower alkyl, or lower alkoxy; the dashed line indicates the optional presence of a double bond; and A is straight or branched chain alkylene of 1-8 carbons; are disclosed. These compounds exhibit antidepressant activity. In addition, these compounds are useful as antiinflammatory agents.

BACKGROUND OF THE INVENTION

Various naphthalimide compounds have been developed for use as dyes and optical brightening agents. Kimura et al., for example, at Chem. Abst., Vol. 62, 11950c, disclose N-[2-piperidinoethyl]-4-methoxy-1,8-naphthalimide (i.e. 6-methoxy-2-[2-(1-piperidinyl)ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione under the current Chem. Abst. nomenclature) as an optical brightening agent. Noguchi et al. in U.S. Pat. No. 3,625,947 disclose 2-[2-(2- or 4-pyridyl)ethyl]-1H-benz[de]isoquinoline-1,3(2H)-diones as fluorescent whitening agents.

Schenker et al. in U.S. Pat. No. 3,247,208 disclose that 1H-benz[de]isoquinoline-1,3(2H)-diones having a (1-substituted-4-piperidinyl) group in the 2-position possess anesthetic properties. Carron et al. in French Pat. No. 2,167,355 disclose that (4-phenyl)piperidine-2,6-diones having an alkylheteroalkyl substituent at the 1-position possess antidepressant activity. Imides having a nitroimidazolyethyl group as an N-substituent and possessing anti-bacterial and anti-protozoal activity are disclosed in U.S. Pat. Nos. 3,642,836 and 3,770,763 to Cusic et al. Certain imido dicarboxylic acid imides possessing various pharmacological properties are disclosed in U.S. Pat. No. 3,560,495 to Frankus et al.

Pharmaceutically active compounds having a 4-(2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-(piperidinyl or 1,2,3,6-tetrahydro-1-pyridinyl) substituent are disclosed by Janssen in U.S. Pat. Nos. 3,161,645, 3,196,157, 3,225,052, 3,318,900, and 3,345,364, by Janssen et al. in U.S. Pat. No. 3,818,017, by Maruyama et al. in U.S. Pat. No. 3,840,529 and by Soudijn et al. in U.S. Pat. No. 3,873,534.

SUMMARY OF THE INVENTION

This invention is directed to new compounds and their pharmaceutically acceptable salts of the formula ##STR2##

The symbols have the following meaning in formula I and throughout this specification.

R¹ and R² are independently selected from hydrogen, halogen, lower alkyl, lower alkoxy, lower alkylthio, nitro, amino, trifluoromethyl, and cyano.

R³ is selected from hydrogen and lower alkyl.

R⁴ and R⁵ are independently selected from hydrogen, halogen, lower alkyl, and lower alkoxy.

A is straight or branched chain alkylene of 1 to 8 carbons.

The dashed line indicates the optional presence of a double bond.

DETAILED DESCRIPTION OF THE INVENTION

The various groups represented by the symbols have the meanings defined below and these definitions are retained throughout this specification.

The lower alkyl groups referred to throughout this specification include straight or branched chain hydrocarbon groups containing 1 to 4 carbons. Examples of the type of groups contemplated are methyl, ethyl, propyl, isopropyl, butyl, etc. The lower alkoxy groups include such lower alkyl groups attached to an oxygen, e.g., methoxy, ethoxy, propoxy, etc. The lower alkylthio group include such lower alkyl groups attached to a sulfur, e.g., methylthio, ethylthio, etc.

Straight or branched chain alkylene of 1 to 8 carbons is intended to include group such as --(CH₂)_(n) -- wherein n is 1 to 8, ##STR3## etc.

Halogen is intended to include chlorine, bromine, fluorine and iodine, with chlorine, bromine and fluorine being preferred and chlorine being most preferred.

Preferred among the compounds of formula I are those of the formula ##STR4## wherein R¹ and R² are independently selected from hydrogen, Cl, Br, F, methyl and methoxy and are located at the 7- or 8-position or 5- or 6-position respectively; R⁴ and R⁵ are independently selected from hydrogen, methyl, methoxy, Cl, Br, and F; R³ is hydrogen or methyl; and A is straight or branched chain alkylene of 2-6 carbons.

Most preferred are the compound of formula Ia wherein R¹, R², R³, R⁴ and R⁵ are hydrogen and A is straight chain alkylene of 2-6 carbons; especially wherein A is --(CH₂)₂ --.

The new compounds of this invention are prepared by the following reactions where A is straight or branched chain alkylene of 2 to 8 carbons.

The substituted naphthalic anhydride of formula II ##STR5## is reacted with an alkanolamine of formula III

    H.sub.2 N--A--OH                                           (III)

to yield the alcohol of formula IV ##STR6##

The alcohol of formula IV is converted to the intermediate of formula V ##STR7## where Y is a leaving group such as tosylate, methane sulfonate or halogen by treating the alcohol with p-toluenesulfonyl chloride, methane sulfonyl chloride, thionyl chloride, thionyl bromide or hydrogen iodide.

The intermediate of formula V is then converted to the final products of formula I by reactions with compounds of the formula ##STR8##

The substituted naphthalic anhydride of formula II can be converted directly to the final products of formula I by reacting the anhydride with compounds of formula VII ##STR9##

The following schematic summarizes the reactions described above.

where A is straight or branched chain alkylene of 2 to 8 carbons ##STR10##

Also, the intermediate of formula V can be prepared by combining a substituted naphthalimide of formula VIII ##STR11## in an organic solvent with a polar organic solvent solution of a base, as for example an alcohol solution of potassium hydroxide, followed by the addition of a solution of the compound of formula IX,

    Y'--A--Y                                                   (IX)

wherein Y' and Y are the same or different and are leaving groups selected from tosylate, methane sulfonate, or halogen and A is a straight or branched chain alkylene of 2 to 8 carbons.

Alternatively, the compounds of formula I wherein A is straight or branched alkylene of 2 to 8 carbons can be prepared by combining the anion of the substituted naphthalimide of formula VIII, described above, with a solution of the compound of formula X, ##STR12## wherein Y is a leaving group as previously defined.

Compounds of formula I where A is --CH₂ -- are prepared by reacting the substituted naphthalimide of formula VIII suspended in a polar organic solvent such as dimethylformamide (DMF) with compounds of formula VI and a source of formaldehyde such as aqueous formaldehyde or paraformaldehyde.

The various starting materials such as the substituted anhydrides of formula II and the alcohols of formula IV and the substituted naphthalimides of formula VIII are known in the art or are readily obtainable by known procedures. Further process details are also provided in the illustrative examples.

The compounds of formula I wherein either or both R¹ and R² are amine are prepared by reducing the corresponding nitro substituted compound with a reducing agent such as hydrogen over a palladium catalyst or a suitable chemical reducing agent. This is preferably done as the last stage in the reaction procedures described above.

Depending on the reaction conditions and the starting materials used, the new compounds are obtained in the free form or in the form of their acid addition salts. The salts thereof can be converted into the free compounds in a known manner such as by reaction with a basic agent. Free bases which may be obtained can be converted into pharmaceutically acceptable acid addition salts by reaction with a variety of acids. Acids useful for preparing these acid-addition salts include, inter alia, inorganic acids, such as the hydrohalic acids (e.g. hydrochloric and hydrobromic acid), sulfuric acid, nitric acid, and phosphoric acid, and organic acids such as maleic, fumaric, tartaric, citric, acetic, benzoic, 2-acetoxybenzoic, salicyclic, succinic, nicotinic, methanesulfonic or cyclohexanesulfamic.

The new compounds of the present invention including the acid addition salts are capable of modifying the central nervous system. When administered to mice, cats, rats, dogs, and other mammalian species in amounts ranging from about 0.5 mg. to about 100 mg. per kg. of body weight per day, these compounds in particular exhibit antidepressant activity. A preferred dosage regimen for optimum results would be from about 1 mg. to about 5 mg. per kg. of body weight per day, and such dosage units are employed so that a total of from about 35 mg. to about 3 g. of active ingredient in single or divided doses are administered in a 24 hour period.

The antidepressant activity of the compounds of formula I is demonstrated by their ability to antagonize tetrabenazine-induced ptosis according to the procedure of Vernier et al. ("The Pharmacodynamics of Amitriptyline", Psychosomatic Medicine, (1962), pages 683-690) and also by their ability to block the reuptake of monoamines in vitro according to the procedure of Horn et al. (Molecular Pharmacology, 7th Ed., (1971), page 66).

The compounds of formula I are also useful as anti-inflammatory agents and may be used, for example, in a manner similar to phenylbutazone or indomethacin. They may be used to decrease joint swelling, tenderness, pain and stiffness in mammalian species, e.g., in conditions such as rheumatoid arthritis. The quantity administered ranges from about 1 mg. to about 15 mg. per kg. of body weight per day.

For any of these pharmaceutical purposes a compound or mixture of compounds of formula I or their pharmaceutically acceptable acid addition salts may be administered orally or parenterally in a conventional dosage form such as tablet, capsule, injectable or the like. These may be conventionally formulated in an oral or parenteral dosage form by compounding with a conventional vehicle, excipient, binder, preservative, stabilizer, flavor or the like as called for by accepted pharmaceutical practice.

The following examples are illustrative of the invention are represent preferred embodiments. Other modifications may be readily produced by suitable variations of the reactions. All temperatures are in the centigrade scale.

EXAMPLE 1 2-[2-[4-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]-ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride (1:1)

a. 2-(2-Hydroxyethyl)-1H-benz[de]isoquinoline-1,3(2H)-dione

50 g. (0.252 mole) of naphthalic anhydride and 16 g. (0.262 mole) of ethanolamine are refluxed for 3 hours in 200 ml. of water (the solution is never complete). After cooling to 25° the water is decanted off and the residue recrystallized from 95% ethanol to yield 47.8 g. of 2-(2-hydroxyethyl)-1H-benz[de]isoquinoline-1,3(2H)-dione; m.p. 172°-173°.

b. 2-(2-Hydroxyethyl)-1H-benz[de]isoquinoline-1,3(2H)-dione, 4-methylbenzenesulfonate ester

52 g. (0.216 mole) of the 2-(2-hydroxyethyl)-1H-benz[de]isoquinoline-1,3(2H)-dione and 100 g. (0.525 mole) of p-toluenesulfonyl chloride are added to 600 ml. of pyridine previously cooled to 5°. The mixture is shaken briefly then allowed to stand overnight at 5°. The mixture is then poured into 3000 ml. of ice and water, stirred for 15 minutes and filtered. The insoluble material is stirred with fresh water, filtered off again and dried overnight at 25° (0.1 mm.) yielding 83 g. of 2-(2-hydroxyethyl)-1H-benz[de]isoquinoline-1,3(2H)-dione, 4-methylbenzenesulfonate ester.

c. 2-[2-[4-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride (1:1)

8.26 g. (0.02 moles) of the ester from part (b), 5.0 g. (0.023 moles) of 1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one and 2.7 g. (0.02 moles) of diisopropylethylamine are refluxed in 500 ml. of toluene for 2 hours. The toluene is evaporated and the residue is taken up in chloroform and washed with 10% KOH. The chloroform layer is shaken with 10% HCl and the resulting yellow precipitate is removed by filtration, washed with water and chloroform, and dried to yield 8.25 g. of crude product. This material is shaken with chloroform and 10% KOH. The layers are separated. The chloroform is evaporated and the residue is recrystallized from CHCl₃ /ethanol to yield 2-[2-[4-(2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione.

This free base is dissolved in hot CHCl₃ /ethanol, excess 3.7N HCl/ethanol is added, and the resulting precipitate is filtered off and dried overnight at 80° (200 mm.) to yield 4.0 g. of 2-[2-[4-(2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]-ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride (1:1); m.p. 326°-328° (dec.).

EXAMPLE 2 2-[2-[4-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)-1,2,3,6-tetrahydro-1-pyridinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H-dione, hydrochloride

Following the procedure of example 1 but substituting an equivalent amount of 1,3-dihydro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one for the 1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one in part (c), one obtains the titled compound.

EXAMPLES 3-13

Following the procedure of example 1 but substituting the alkanolamine shown in Col. I for the ethanolamine in part (a), the following products are obtained wherein A is the alkylene shown in Col. II.

    ______________________________________                                          ##STR13##                                                                     Ex.  Col. I              Col. II                                               ______________________________________                                         3    H.sub.2 N(CH.sub.2).sub.3OH                                                                        (CH.sub.2).sub.3                                      4    H.sub.2 N(CH.sub.2).sub.4OH                                                                        (CH.sub.2).sub.4                                      5    H.sub.2 N(CH.sub.2).sub.5OH                                                                        (CH.sub.2).sub.5                                      6    H.sub.2 N(CH.sub.2).sub.6OH                                                                        (CH.sub.2).sub.6                                      7    H.sub.2 N(CH.sub.2).sub.7OH                                                                        (CH.sub.2).sub.7                                      8    H.sub.2 N(CH.sub.2).sub.8OH                                                                        (CH.sub.2).sub.8                                            ##STR14##                                                                                          ##STR15##                                            10                                                                                   ##STR16##                                                                                          ##STR17##                                            11                                                                                   ##STR18##                                                                                          ##STR19##                                            12                                                                                   ##STR20##                                                                                          ##STR21##                                            13                                                                                   ##STR22##                                                                                          ##STR23##                                            ______________________________________                                    

Similarly, by employing the alkanolamines of examples 3-13 within the procedure of example 2 other compounds within the scope of the invention are obtained.

EXAMPLES 14-26

Following the procedure of example 1 but substituting for the 1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one in part (c), one of the following compounds:

1,3-dihydro-1-methyl-3-(4-piperidinyl)-2H-benzimidazol-2-one;

1,3-dihydro-1-ethyl-3-(4-piperidinyl)-2H-benzimidazol-2-one;

1,3-dihydro-1-(t-butyl)-3-(4-piperidinyl)2H-benzimidazol-2-one;

6-chloro-1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one;

5-bromo-1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one;

1,3-dihydro-5-fluoro-1-(4-piperidinyl)-2H-benzimidazol-2-one;

5,6-dichloro-1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one;

1,3-dihydro-5-methyl-1-(4-piperidinyl)-2H-benzimidazol-2-one;

1,3-dihydro-5,6-dimethyl-1-(4-piperidinyl)-2H-benzimidazol-2-one;

6-chloro-1,3-dihydro-1-methyl-3-(4-piperidinyl)-2H-benzimidazol-2-one;

4-chloro-1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one;

1,3-dihydro-5-methoxy-1-(4-piperidinyl)-2H-benzimidazol-2-one; and

1,3-dihydro-6-ethoxy-1-(4-piperidinyl)-2H-benzimidazol-2-one

one obtains the following products:

2-[2-[4-(2,3-dihydro-2-oxo-3-methyl-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-2-oxo-3-ethyl-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-2-oxo-3-t-butyl-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(6-chloro-2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(5-bromo-2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H9-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-5-fluoro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(5,6-dichloro-2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-5-methyl-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-5,6-dimethyl-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(6-chloro-2,3-dihydro-3-methyl-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(4-chloro-2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-5-methoxy-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-6-ethoxy-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride; respectively.

Similarly, by employing the alkanolamines of examples 3-13 within the procedure of examples 14-26, other compounds within the scope of the invention are obtained.

EXAMPLES 27-39

Following the procedure of example 2 but substituting for the 1,3-dihydro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one, one of the following compounds:

1,3-dihydro-1-methyl-3-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

1,3-dihydro-1-ethyl-3-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

1,3-dihydro-1-t-butyl-3-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

6-chloro-1,3-dihydro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

5-bromo-1,3-dihydro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

1,3-dihydro-5-fluoro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

5,6-dichloro-1,3-dihydro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

1,3-dihydro-5-methyl-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

1,3-dihydro-5,6-dimethyl-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

6-chloro-1,3-dihydro-1-methyl-3-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

4-chloro-1,3-dihydro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

1,3-dihydro-5-methoxy-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one; and

1,3-dihydro-6-ethoxy-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one;

one obtains the following products:

2-[2-[4-(2,3-dihydro-3-methyl-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-3-ethyl-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-3-t-butyl-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(6-chloro-2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(5-bromo-2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-5-fluoro-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(5,6-dichloro-2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-5-methyl-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-5,6-dimethyl-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(6-chloro-2,3-dihydro-3-methyl-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(4-chloro-2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride;

2-[2-[4-(2,3-dihydro-5-methoxy-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride; and

2-[2-[4-(2,3-dihydro-6-ethoxy-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]ethyl]-1H-benz[de]-isoquinoline-1,3(2H)-dione, hydrochloride; respectively.

Similarly, by employing the alkanolamines of examples 3- 13 within the procedure of examples 27-39, other compounds within the scope of the invention are obtained.

EXAMPLE 40 2-[4-[4-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]-butyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride (1:1)

a. 2-(4-Bromobutyl)-1H-benz[de]isoquinoline-1,3(2H)-dione

100 g. (0.5 mole) of 1,8-naphthalimide is suspended in 2100 ml. of dimethylformamide and the mixture is heated to 90° to form a complete solution. A solution of 36.3 g. (0.55 mole) of potassium hydroxide (85%) in 100 ml. of methanol is added resulting in the immediate formation of a yellow precipitate. The resulting mixture is stirred for 1 hour at 90° and cooled to 25°. 245 g. (1.0 mole) of 1,4-dibromobutane is added and the mixture is again heated to 90° and stirred for an additional hour. A precipitate remains in the mixture but is more granular than the initial material. The reaction mixture is cooled and the precipitate filtered off. The solvent is removed under vacuum and the residue is diluted with 500 ml. of hexane immediately precipitating crude 2-(4-bromobutyl)-1H-benz[de]isoquinoline-1,3(2H)-dione. The precipitate is filtered off, washed with fresh hexane and dried for 2 hours at 50° (0.1 mm.) to yield 2-(4-bromobutyl)-1H-benz[de]isoquinoline-1,3(2H)-dione. An analytically pure sample is prepared by dissolving the above product in hot 95% ethanol and recrystallizing by allowing the solution to cool to 25°. The resulting precipitate is dried for two hours at 50° (0.1 mm.) to yield pure 2-(4-bromobutyl)-1H-benz[de]isoquinoline-1,3(2H)-dione, m.p. 113°-115°.

b. 2-[4-[4-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]butyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride

An equimolar mixture of the bromide from part (a) and 1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one are refluxed with excess sodium carbonate in 200 ml. of n-butanol for 24 hours. The n-butanol is evaporated and the residue is taken up in chloroform and water. The aqueous layer is washed with chloroform and the chloroform layers are combined, washed with water, filtered and evaporated. The residue is taken up in hot ethanol, filtered, and 5 ml. of concentrated HCl is added to form a precipitate of 2-[4-[4-(2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]butyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride.

EXAMPLE 41 2-[4-[4-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]butyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride

Following the procedure of example 40 but substituting an equivalent amount of 1,3-dihydro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one for the 1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one in part (b), one obtains the titled compound.

Similarly, the procedure of example 40 can be employed to prepare the compounds of examples 1-39.

EXAMPLE 42 2-[1-[4-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]-methyl]-1H-benz[de]isoquinoline-1,3(2H)-dione

An equimolar mixture of 1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one, aqueous formaldehyde and 1,8-naphthalimide is suspended in a small amount of dimethylformamide and the mixture is heated until dissolution is complete. The solution is allowed to stand at room temperature and the resulting precipitate is filtered off and dried to yield 2-[1-[4-(2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]methyl]-1H-benz[de]isoquinoline-1,3(2H)-dione.

Similarly, by substituting for the 1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one the various substituted reactants of examples 14-26, other compounds within the scope of invention are obtained.

EXAMPLE 43 2-[1-[4-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]methyl]-1H-benz[de]isoquinoline-1,3-(2H)-dione

An equimolar mixture of 1,3-dihydro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one, aqueous formaldehyde, and 1,8-naphthalimide is suspended in a small amount of dimethylformamide and the mixture is heated until dissolution is complete. The solution is allowed to stand at room temperature and the resulting precipitate is filtered off and dried to yield 2-[1-[4-(2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-(1,2,3,6-tetrahydro-1-pyridinyl)]methyl]-1H-benz[de]isoquinoline-1,3(2H)-dione.

Similarly, by substituting for the 1,3-dihydro-1-(1,2,3,6-tetrahydro-4-pyridinyl)-2H-benzimidazol-2-one the various substituted reactants of examples 27-39, other compounds within the scope of the invention are obtained.

EXAMPLES 44-69

Following the procedure of example 1 but substituting for the 2-(2-hydroxyethyl)-1H-benz[de]isoquinoline-1,3(2H)-dione, 4-methylbenzenesulfonate ester the ester shown in Col. I one obtains the product shown in Col. II.

    __________________________________________________________________________     Col. I          Col. II                                                        __________________________________________________________________________      ##STR24##                                                                                      ##STR25##                                                     Ex. X.sup.1                                                                              X.sup.2                                                                              X.sup.3                                                                              X.sup.4                                                                              X.sup.5                                                                              X.sup.6                                      __________________________________________________________________________     44  H     H     Br    H     H     H                                            45  H     Cl    H     H     H     H                                            46  H     Br    H     H     H     H                                            47  H     F     H     H     H     H                                            48  H     I     H     H     H     H                                            49  H     Cl    H     H     Cl    H                                            50  Br    H     H     H     H     H                                            51  H     H     Cl    Cl    H     H                                            52  H     H     CH.sub.3                                                                             H     H     H                                            53  H     H     C.sub.2 H.sub.5                                                                      H     H     H                                            54  H     H     i-C.sub.3 H.sub.7                                                                    H     H     H                                            55  H     H     CH.sub.3                                                                             CH.sub.3                                                                             H     H                                            56  H     H     OCH.sub.3                                                                            H     H     H                                            57  H     H     OC.sub.2 H.sub.5                                                                     H     H     H                                            58  H     H     OC.sub.3 H.sub.7                                                                     H     H     H                                            59  H     H     OCH.sub.3                                                                            OCH.sub.3                                                                            H     H                                            60  H     NO.sub.2                                                                             H     H     H     H                                            61  H     H     NO.sub.2                                                                             H     H     H                                            62  H     CF.sub.3                                                                             H     H     H     H                                            63  H     H     CF.sub.3                                                                             H     H     H                                            64  H     CN    H     H     H     H                                            65  H     H     CN    H     H     H                                            66  H     H     NH.sub.2                                                                             H     H     H                                            67  H     NH.sub.2                                                                             H     H     H     H                                            68  H     SC.sub.3 H.sub.7                                                                     H     H     H     H                                            69  H     H     SCH.sub. 3                                                                           H     H     H                                            __________________________________________________________________________

Similarly, by employing the ester of Col. I of examples 44-69 in the procedure of examples 2 and 14-39, other compounds within the scope of this invention are prepared.

Similarly, by following the procedure of examples 3-13, but employing a substituted 1,8-naphthalic anhydride of formula II wherein the substituents are those listed under the headings X¹, X², X³, X⁴, X⁵, and X⁶ in examples 44-69, other compounds within the scope of the invention are prepared. Also, by following the procedures of examples 40-43 but employing a substituted 1,8-naphthalimide of formula VIII wherein the substituents are those listed under the headings X¹, X², X³, X⁴, X⁵, and X⁶ in examples 44 to 69, other compounds within the scope of this invention are prepared. 

What is claimed is:
 1. A compound of the formula: ##STR26## wherein R¹ and R² are independently selected from the group consisting of hydrogen, halogen, lower alkyl, lower alkoxy, lower alkylthio, nitro, amino, trifluoromethyl and cyano; R³ is hydrogen or lower alkyl, R⁴ and R⁵ are independently selected from the group consisting of hydrogen, lower alkyl, lower alkoxy and halogen; and A is straight or branched chain alkylene of 1 to 8 carbons; the dashed line indicates the optional presence of a double bond; and a pharmaceutically acceptable acid addition salt thereof.
 2. The compound of claim 1 having the formula: ##STR27## wherein R¹, R², R³, R⁴, R⁵ and A are as defined in claim 1, and a pharmaceutically acceptable acid addition salt thereof.
 3. The compound of claim 2 wherein A is straight or branched chain alkylene of 2 to 6 carbons.
 4. The compound of claim 2 having the formula: ##STR28## wherein R¹ is located at either the 7- or 8-position and R² is located at either the 5- or 6-position and R¹ and R² are independently selected from the group consisting of hydrogen, Cl, Br, F, methyl and methoxy; R³ is hydrogen or methyl; R⁴ and R⁵ independently selected from the group consisting of hydrogen, methyl, methoxy, Cl, Br, and F; and A is straight or branched chain alkylene of 1- 6 carbons; and a pharmaceutically acceptable acid addition salt thereof.
 5. The compound of claim 4 wherein A is straight or branched chain alkylene of 2 to 6 carbons.
 6. The compound of claim 5 wherein R¹, R², R³, R⁴ and R⁵ are hydrogen and A is straight chain alkylene of 2 to 6 carbons.
 7. The compound of claim 6 wherein A is --(CH₂)₂ --.
 8. The compound of claim 7 having the name 2-[2-[4-(2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl]-1H-benz[de]isoquinoline-1,3(2H)-dione, hydrochloride (1:1).
 9. The compound of claim 6 wherein A is --(CH₂)₃ --.
 10. The compound of claim 6 wherein A is --(CH₂)₄ --.
 11. The compound of claim 6 wherein A is --(CH₂)₅ --.
 12. The compound of claim 6 wherein A is --(CH₂)₆ --.
 13. The compound of claim 1 having the formula ##STR29## wherein R¹, R², R³, R⁴, R⁵ and A are as defined in claim 1, and a pharmaceutically acceptable acid addition salt thereof.
 14. The compound of claim 13 wherein A is straight or branched chain alkylene of 2 to 6 carbons.
 15. The compound of claim 13 having the formula ##STR30## wherein R¹ is located at the 7- or 8-position and R² is located at the 5- or 6-position and R¹ and R² are independently selected from the group consisting of hydrogen, Cl, Br, F, methyl and methoxy; R³ is hydrogen or methyl; R⁴ and R⁵ independently selected from the group consisting of hydrogen, methyl, methoxy, Cl, Br, and F; and A is straight or branched chain alkylene of 1-6 carbons; and a pharmaceutically acceptable acid addition salt thereof.
 16. The compound of claim 15 wherein A is straight or branched chain alkylene of 2 to 6 carbons.
 17. The compound of claim 16 wherein R¹, R², R³, R⁴ and R⁵ are hydrogen and A is straight chain alkylene of 2 to 6 carbons.
 18. The compound of claim 16 wherein A is --(CH₂)₂ --.
 19. The compound of claim 16 wherein A is --(CH₂)₃ --.
 20. The compound of claim 16 wherein A is --(CH₂)₄ --.
 21. The compound of claim 16 wherein A is --(CH₂)₅ --.
 22. The compound of claim 16 wherein A is --(CH₂)₆ --.
 23. A composition useful for treating depression in mammals comprising as the active ingredients from about 0.5 to about 100 mg. per kg. of body weight of the mammal being treated of a compound or mixtures of compounds of claim 1 and a pharmaceutically acceptable carrier.
 24. The method of treating depression in mammals comprising administering an effect amount of the composition of claim
 23. 